1. Field of the Invention
The present invention relates to improving the energy efficiency of a washing machine.
2. Description of the Related Art
In general, washing machines are devices for removing dust and dirt from laundry using a chemical dissolution operation involving the use of water and detergent or using a physical operation such as friction between water and the laundry.
Washing machines are classified into a vortex-type washing machine, which includes a washing machine standing upright, generates a vortex in wash water contained in the washing tub, and thus washes laundry using friction between water and laundry, and a drum-type washing machine, which includes a drum and a lifter and washes laundry loaded in the drum using physical impact generated when the laundry is dropped after being lifted up by the lifter upon the rotation of the drum.
The performance of a washing machine is considerably affected by whether detergent is well dissolved in wash water and whether laundry is soaked in wash water to the extent that dust and dirt can be easily separated from the laundry. Thus, in order to improve the washing efficiency of a washing machine, the temperature of wash water may be increased. However, since a considerable amount of thermal energy is generally required to increase the temperature of wash water, it is deemed inefficient to increase the temperature of wash water in terms of power consumption.
In the meantime, in order to improve the thermal efficiency of a washing machine, a heat generator with a high thermal efficiency may be used. However, the introduction of such additional device to an existing washing machine may result in an increase in the price of a washing machine. Therefore, it is necessary to develop ways to improve the thermal efficiency of a washing machine without incurring additional costs.